Coherence and Dephasing in Self-Assembled Quantum Dots
نویسندگان
چکیده
We measured dephasing times in InGaAlAs selfassembled quantum dots at low temperature using degenerate four-wave mixing. At OK, the coherence time of the quantum dots is lifetime limited, whereas at finite temperatures pure dephasing by exciton-phonon interactions governs the quantum dot coherence. The inferred homogeneous line widths are significantly smaller than the line widths usually observed in the photoluminescence from single quantum dots indicating an additional inhomogeneous broadening mechanism in the latter. Quantum dots; exciton coherence; dephasing; homogeneous and inhomogeneous line widths.
منابع مشابه
Long lived coherence in self-assembled quantum dots.
We report measurements of ultralong coherence in self-assembled quantum dots. Transient four-wave mixing experiments at 5 K show an average dephasing time of 372 ps, corresponding to a homogeneous linewidth of 3.5 microeV, which is significantly smaller than the linewidth observed in single-dot luminescence. Time-resolved luminescence measurements show a lifetime of the dot ground state of 800 ...
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